On an air cooled engine film thickness is your friend. I use a Euro 0W-40 in mine, that accounts for winter starting and for summer needs. No way on earth I'd use a 20-grade in a mission critical device like this. If I were in the south or Florida I'd be using a 50-grade.
Generac 5W20 Low Ash (GEO) oil for Generators
- Thread starter cao-2000
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Just bought the 18/17KW model #7226 with install planned for this spring using natural gas.
https://www.generac.com/generaccorp...-7036/generac-owner-manual-10kw-24kw-en_1.pdf
The online manual on Page 27 states:
“All Generac oil kits meet minimum American Petroleum Institute (API) Service Class SJ, SL, or better. Do not use special additives.
Synthetic SAE 5W-30 for all temperature ranges.”
Was told by representative on the phone it shipped with conventional 5w30 oil in it, and that should be run for the initial 25 hours then can be switched over to synthetic. I asked if it was a break-in oil, although they couldn’t confirm that specifically.
In my temperature range for a Michigan, Mobil 1 Euro 0w40 has ran fine in my old portable Homelite gen. If wanting to follow the manual for warranty purposes a 5w30 SL rated Castrol Edge Euro, Total Quartz 9000 Energy, Mobil 1 ESP or Rotella T5 Multi Vehicle 5w30 should have near a 3.5 HT/HS. The Castrol Euro A3B4 0w30 looks really stout
Outside of warranty a 0w40 Euro or sooner depending how the 5w30 holds up after the first few early changes.
https://www.generac.com/generaccorp...-7036/generac-owner-manual-10kw-24kw-en_1.pdf
The online manual on Page 27 states:
“All Generac oil kits meet minimum American Petroleum Institute (API) Service Class SJ, SL, or better. Do not use special additives.
Synthetic SAE 5W-30 for all temperature ranges.”
Was told by representative on the phone it shipped with conventional 5w30 oil in it, and that should be run for the initial 25 hours then can be switched over to synthetic. I asked if it was a break-in oil, although they couldn’t confirm that specifically.
In my temperature range for a Michigan, Mobil 1 Euro 0w40 has ran fine in my old portable Homelite gen. If wanting to follow the manual for warranty purposes a 5w30 SL rated Castrol Edge Euro, Total Quartz 9000 Energy, Mobil 1 ESP or Rotella T5 Multi Vehicle 5w30 should have near a 3.5 HT/HS. The Castrol Euro A3B4 0w30 looks really stout
Outside of warranty a 0w40 Euro or sooner depending how the 5w30 holds up after the first few early changes.
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I chose HPL CK-4 HDEO 5w40 Cold Climate (PAO) for my generator. Covers all possible operating conditions where I live.
Castrol Euro 5W30 would be an excellent choice.
Pennzoil Platinum Euro L 5W30 would be another good choice.
I currently have FRAM Synthetic 5W30 in my 22KW. I’ll probably switch to a 5W30 Euro on the next change.
Finding aftermarket oil filters locally is my biggest problem. I’d like to run FRAM TG4386. I may have to settle on the NAPA Gold 7145.
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I for sure learned something new. Always used and seen generators run 5 and 10w30.
I just changed the oil in my 22kw Generac. I went with Shell Rotella t6 5w40. My owners manual says to use a
5W30 synthetic. I don't see a problem going to a 5w40 synthetic.
Do you actually think that they would pull an oil sample? I don't. Do the maintenance required and log it. It doesn't get real cold where I live. If I lived up north, I would probably run a 5W30. Get a paint pen and put date and hours on the filter at each oil change.
Where I used to work I was charged with maintaining a good sized Kohler backup genset. It was powered with the aftermarket version of the Chevy 305 and run on the bottle. (propane). Liquid injected with computer control made a nice running machine. Kohler did not recommend any special oil for it. I used our bulk Chevron Supreme 10w 30. No issues ever, even after a several day run. Same with our Cat forklift running a Mitsubishi 4 cyl. Use quality oil in the correct grade for your climate and all will be good.
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